Circular No. 8298
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)POSSIBLE SUPERNOVA ASSOCIATED WITH Q0957+561
C. Y. Peng and C. D. Impey, University of Arizona; H.-W. Rix,
Max-Planck-Institut fuer Astronomie, Heidelberg; C. S. Kochanek,
Ohio State University; E. E. Falco, J. Lehar, and B. A. McLeod,
Harvard-Smithsonian Center for Astrophysics; and C. R. Keeton,
University of Chicago, report the discovery, on 28 images taken
over 9 hr on Feb. 4 with the Hubble Space Telescope NICMOS camera
2, of a possible supernova (infrared mag H = 22.9 +/- 0.1) in the
gravitational-lens system Q0957+561. The new object is located
about 1".10 east and 0".08 north from image 'B' of the quasar (R.A.
= 10h01m20s.8, Decl. = +55o53'50", equinox 2000.0). A similar
frame taken on 1998 May 30 shows no stellar object at this location
(limiting mag H = 24). The new object may be located in the
outskirts of the lensing galaxy (z = 0.36) or in the lensed host
galaxy of the quasar (z = 1.41). If the possible supernova is
lensed, its intrinsic magnitude is roughly 22.4 after correcting
the lens magnification, or M_R about -20.4. The new object appears
near the trailing image B of the quasar; thus, while one would
expect a counter image of the possible supernova to appear near the
leading 'A' image, it would be 173 days (rest frame) further along
the light curve and would be too faint to detect. And, in fact,
one sees no counterpart near the 'A' image.
TRANSITS OF MARS I AND II
J. Bell, Cornell University; M. Lemmon, Texas A&M University;
and M. Wolff, Space Science Institute; and the Mars Exploration
Rover 'Athena' Science Team, report the imaging of transits of Mars
I (Phobos) and Mars II (Deimos) across the sun with the Pancam 1-cm
f/20 binocular CCD camera (+ solar neutral-density 5 filter;
passband 880 +/- 20 nm; exposure lengths 0.06 and 0.10 s, taken at
10-s intervals) onboard the 'Opportunity' Rover craft located on
the planet's surface at longitude 354.47417 deg east and latitude
1.94828 deg south. This is apparently the first direct imaging of
a natural-satellite transit from the surface of another planet.
The sun is approximately 20 pixels in diameter on the images, with
Mars I and II having apparent diameters of approximately 10-13 and
2 pixels, respectively. Mars II was already in transit when the
first image was obtained on Mar. 4.12773 UT, was approximately at
mid-transit on the Mar. 4.12785 image, and was between third and
fourth contacts on the Mar. 4.12819 image. Mars I was possibly
near first contact on the image of Mar. 7.11556, was near mid-
transit on Mar. 7.11567, and was near fourth contact on Mar.
7.11579.
(C) Copyright 2004 CBAT2004 March 8 (8298) Daniel W. E. Green